1. Field of the Invention
The object of the invention is an advantageous way to connect electronics equipment for instance to a mobile station via a standardised interface for short-range wireless data communication, and a data communication device connected to this standardised interface.
2. Brief Description of Related Developments
It is previously known to connect a portable computer and a mobile station 1 via an infrared (IR) link to a printer 4 shown in FIG. 1. Then an IR transmitter/receiver 2, 3 is constructed in the devices 1, 4 being parties of the data communication, and routines required by the data communication has been designed in the software of the devices 1, 4.
There are also known mobile communications applications developed particularly in connection with portable data processing equipment, such as laptop PCs. In these applications at least the transmitter/receiver functions of the mobile station are realised in a PC Card. A PC Card is an expansion card with an interface to the electronic device, such as a computer, which interface is defined by the PCMCIA standard (Personal Computer Memory Card International Association). For instance an expansion card containing a transmitter/receiver of a GSM mobile station is used for data communication in order to connect the electronic device to the GSM network. However, the use of the application requires pre-installed software in the electronic device.
There is also known a low power radio frequency (LPRF) or a short-range radio frequency link, which replaces a connection cable between electronic devices, and which is defined at least by the Bluetooth Special Interest Group. This concerns an unfinished industry standard where the communication link is intended to be realised at a vacant ISM frequency (Industrial, Scientific, Medical) of 2,45 GHz and at a power of 0 dBm or 1 mW, whereby the range is 10 meters and the data transmission rate is 721 kbit/s. The link uses frequency hopping and a time divided duplex connection. Reference: Codename Bluetooth, A Global Specification for Wireless Connectivity, Bluetooth Special Interest Group, www.bluetooth.com, 1988.
It is also known to expand the features of mobile stations with the aid of expansion cards. Then for instance a digital camera is connected to the mobile station.
A problem in known devices is that they require identification of the expansion card and co-operation in the electronic device. An electronic device connecting a mobile station to a cellular radio network requires special software for the data communication link and a sufficient processor capacity.